/*
 * Copyright (c) 2007, 2015, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
package com.sun.org.apache.xml.internal.security.keys.keyresolver.implementations;

import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.cert.X509Certificate;
import javax.crypto.SecretKey;
import com.sun.org.apache.xml.internal.security.keys.keyresolver.KeyResolverException;
import com.sun.org.apache.xml.internal.security.keys.keyresolver.KeyResolverSpi;
import com.sun.org.apache.xml.internal.security.keys.storage.StorageResolver;
import com.sun.org.apache.xml.internal.security.utils.Constants;
import com.sun.org.apache.xml.internal.security.utils.XMLUtils;
import org.w3c.dom.Element;

/**
 * Resolves a single Key based on the KeyName.
 */
public class SingleKeyResolver extends KeyResolverSpi {

  /**
   * {@link org.apache.commons.logging} logging facility
   */
  private static java.util.logging.Logger log =
      java.util.logging.Logger.getLogger(SingleKeyResolver.class.getName());

  private String keyName;
  private PublicKey publicKey;
  private PrivateKey privateKey;
  private SecretKey secretKey;

  /**
   * Constructor.
   */
  public SingleKeyResolver(String keyName, PublicKey publicKey) {
    this.keyName = keyName;
    this.publicKey = publicKey;
  }

  /**
   * Constructor.
   */
  public SingleKeyResolver(String keyName, PrivateKey privateKey) {
    this.keyName = keyName;
    this.privateKey = privateKey;
  }

  /**
   * Constructor.
   */
  public SingleKeyResolver(String keyName, SecretKey secretKey) {
    this.keyName = keyName;
    this.secretKey = secretKey;
  }

  /**
   * This method returns whether the KeyResolverSpi is able to perform the requested action.
   *
   * @return whether the KeyResolverSpi is able to perform the requested action.
   */
  public boolean engineCanResolve(Element element, String baseURI, StorageResolver storage) {
    return XMLUtils.elementIsInSignatureSpace(element, Constants._TAG_KEYNAME);
  }

  /**
   * Method engineLookupAndResolvePublicKey
   *
   * @return null if no {@link PublicKey} could be obtained
   */
  public PublicKey engineLookupAndResolvePublicKey(
      Element element, String baseURI, StorageResolver storage
  ) throws KeyResolverException {
    if (log.isLoggable(java.util.logging.Level.FINE)) {
      log.log(java.util.logging.Level.FINE, "Can I resolve " + element.getTagName() + "?");
    }

    if (publicKey != null
        && XMLUtils.elementIsInSignatureSpace(element, Constants._TAG_KEYNAME)) {
      String name = element.getFirstChild().getNodeValue();
      if (keyName.equals(name)) {
        return publicKey;
      }
    }

    log.log(java.util.logging.Level.FINE, "I can't");
    return null;
  }

  /**
   * Method engineResolveX509Certificate
   *
   * @inheritDoc
   */
  public X509Certificate engineLookupResolveX509Certificate(
      Element element, String baseURI, StorageResolver storage
  ) throws KeyResolverException {
    return null;
  }

  /**
   * Method engineResolveSecretKey
   *
   * @return resolved SecretKey key or null if no {@link SecretKey} could be obtained
   */
  public SecretKey engineResolveSecretKey(
      Element element, String baseURI, StorageResolver storage
  ) throws KeyResolverException {
    if (log.isLoggable(java.util.logging.Level.FINE)) {
      log.log(java.util.logging.Level.FINE, "Can I resolve " + element.getTagName() + "?");
    }

    if (secretKey != null
        && XMLUtils.elementIsInSignatureSpace(element, Constants._TAG_KEYNAME)) {
      String name = element.getFirstChild().getNodeValue();
      if (keyName.equals(name)) {
        return secretKey;
      }
    }

    log.log(java.util.logging.Level.FINE, "I can't");
    return null;
  }

  /**
   * Method engineResolvePrivateKey
   *
   * @return resolved PrivateKey key or null if no {@link PrivateKey} could be obtained
   * @inheritDoc
   */
  public PrivateKey engineLookupAndResolvePrivateKey(
      Element element, String baseURI, StorageResolver storage
  ) throws KeyResolverException {
    if (log.isLoggable(java.util.logging.Level.FINE)) {
      log.log(java.util.logging.Level.FINE, "Can I resolve " + element.getTagName() + "?");
    }

    if (privateKey != null
        && XMLUtils.elementIsInSignatureSpace(element, Constants._TAG_KEYNAME)) {
      String name = element.getFirstChild().getNodeValue();
      if (keyName.equals(name)) {
        return privateKey;
      }
    }

    log.log(java.util.logging.Level.FINE, "I can't");
    return null;
  }
}
